"For the sake of all the struggling girls all over America, who read Seventeen and think these fake images are what they should be, I'm stepping up. I know how hurtful these Photoshopped images can be. I'm a teenage girl, and I don't like what I see. None of us do. Will you join us by signing this petition and asking Seventeen to take a stand as well and commit to one unaltered photo spread a month?" the petition concludes.

Seventeen editors responded to the pressure and this week announced a new "Body Peace Treaty" which promises to not alter girls' faces or body shapes in its pages and to celebrate every kind of beauty, the New York Timesreports.

"Seventeen listened! They're saying they won't use Photoshop to digitally alter their models! This is a huge victory, and I'm so unbelievably happy," Bluhm writes in a message to her supporters, encouraging them to sign a new petition asking the same from Teen Vogue.

"Another petition is being started by SPARK activists Emma and Carina, targeting Teen Vogue and I will sign it. If we can be heard by one magazine, we can do it with another. We are sparking a change!"

While some photo editing will still be done — removing flyaway hairs or severe wrinkles in clothing, for example — the magazine's Tumblr site will document photo shoots and explain the edits.

Earlier this year, Glamour magazine pledged to tone down the retouching in its spreads, going as far as "asking photographers we hire not to manipulate body size in the photos we commission, even if a celebrity or model requests a digital diet (alas, it happens)."